The Adaptive Period.

This style runs true to size. Please order your most standard size.

You can see our size chart here.

Our Fabrics

Body: 94% Polyester Brushed Microfiber with 6% Spandex Jersey

Lining: 95% organic cotton, 5% spandex

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Personal message from soil: I know it’s highly unusual to get a message from soil but in this case, I just had to say thank you. Just by using one pair of Period underwear, you’re saving the natural world from 9 tampons or 4 pads being thrown away and (because they don’t biodegrade) polluting the Earth for generations. From me and all my microbes - thank you. 

This style is intended for teenagers or petite adults and runs true to size. 

Teens should order their most standard size. 

A petite women's extra small can comfortably fit in a teen medium.

A petite women's small can comfortably fit in a teen large.

You can see our size chart here.

Our Fabrics

Body: 94% Nylon Brushed Microfiber with 6% Spandex Jersey

Lining: 95% organic cotton, 5% spandex

Absorbent Layer: 100% Polyester  

Leak Resistant Layer: 100% Polyester PUL

How to take care of your Period.

Rinse for a few seconds.

Either hand wash and hang dry, or add to the laundry pile.

Regular wash, no bleach.

Tumble dry low or hang dry.

Do not dry clean.

Each pair of Period. underwear can hold up to 9 tampons worth of blood.

Check out our absorbency test video here.

You can see the length of the absorbent panel here.

How long will one pair of Period. last?

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days, including evenings. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

Message from an Oak Tree: Hellooo. I’m a 100 year old oak tree. I live near a landfill and 80 years ago, I saw a tampon get thrown away. Guess what? It’s still there! Still decomposing! I can’t believe it. All the pads and tampons that people have thrown away are all there. And it’s so gross! I used to look out at fields and meadows and woodland. And now I just see decomposing bad products that will taken another hundred years to degrade. I have to confess, I started to lose a little faith in humans. Then you came along. Just by wearing one pair of Period just once, you’ve stopped 2 pads or 4 tampons from being in my eye line. Thank you!